#include<stdio.h>

void func(void *p);

int main()
{
	char num = 'a';
	printf("input a character :\n");
	scanf("%c",&num);
	
	printf("num = %c\n",num);
	
	func(&num);
	
	printf("num = %c\n",num);
	
	return 0;
}

void func(void *p)
{
	if(*(char *)p >='A'&&*(char *)p <= 'Z')
		{
			*(char *)p = *(char *)p + 32;
		}
	else if(*(char *)p >= 'a'&&*(char *)p <= 'z')
		{
			*(char *)p = *(char *)p - 32;
		}
		
	else if(*(char *)p >= '0'&&*(char *)p <= '9') 
		{
			
			printf("num = %d",48 - *(char *)p);
		}
	
}
